Alkali-treated cocoa powder has heretofore been prepared by soaking cacao beans, cacao nibs, cacao mass, cacao flakes or cocoa powder in an alkali solution containing alkalis such as carbonates, hydrogencarbonates, and hydroxides of ammonia, magnesium, sodium, and potassium, drying the above-treated material, and then grinding it. In the case of cacao nibs and cacao beans, they are ground to yield cacao mass and, thereafter, the cacao mass is squeezed and ground to yield cocoa powder. The thus-produced cocoa powder, however, contains about 5 to 20% by weight of coarse particles having a particle size of 25.mu. or more even if ground using a high-speed hammer mill and, therefore, when drunk as a cocoa drink, an undesirable "sandy" taste and feel results. This means that the cocoa powder contains a large amount of coarse particles insoluble in water or hot water.
Cacao butter made by squeezing cacao beans, cacao nibs, and cacao mass which have been subjected to an alkali treatment as described above has an "alkali" odor and cannot be utilized at all as an oil to be added in the production of chocolate unless it is subjected to a treatment to remove the odor.
Japanese Patent Application (OPI) No. 54957/76 (the term "OPI" as used herein refers to a "published unexamined Japanese patent application") discloses a method of producing a chocolate drink in which cacao nibs produced by the usual method are crushed and finely ground without application of an alkali treatment to produce cacao mass, water is added to the cacao mass in an amount of from 5 to 10 times by weight, the resulting mixture is heated to extract an effective components, solids are removed from the mixture, and the thus-obtained aqueous solution serves as a chocolate drink. This method, however, has various disadvantages. For example, since an alkali treatment is not employed in this method, the color of the solution is pale; a light brown color which is characteristic of a cocoa drink is not achieved. Furthermore, it has a strong acid taste and good flavor characteristic of cocoa does not arise. In general, tasteful substances originally insoluble in water are rendered water-soluble by use of an alkali treatment. That is, in accordance with this method, the flavorful substances are not rendered soluble in water because an alkali treatment is not employed. Thus, the amount of the extract is small and the yield is low. Furthermore, the cell walls of the cacao mass are not broken since the mass is not subjected to an alkali treatment. Thus, a large quantity of energy is needed in squeezing the cacao butter.
In addition, the following two methods are generally used to squeeze cacao butter. One method is to squeeze cacao nibs, which have not been subjected to an alkali treatment, using an expeller, and the other method is to squeeze cacao mass, which has been alkali-treated, using a cocoa press. In both of the methods, however, it is not possible to squeeze out all the oil present in the cacao mass. Usually about 10% by weight of cacao butter remains in the cacao mass. Cacao butter obtained from the alkali-treated cacao mass has a strong unpleasant odor and therefore cannot be added to chocolate products unless a deodorizing treatment is applied.
It is also known that cacao butter can be obtained by extraction with a solvent, such as hexane. In this method, however, a process to separate the cacao butter from the solvent after the extraction inevitably becomes complicated. Another disadvantage is that the extraction using hot water of cacao butter from the cacao mass, which has not been subjected to an alkali treatment, results in a low yield.